Uploading a world

Option A — via SFTP (recommended for big worlds)

1. Stop the server (panel → Stop).
2. Connect with SFTP (panel → Settings → SFTP Details).
3. Upload the world folder (the one containing level.dat) to the server root.
4. Set the folder name in server.properties — see below.

Option B — via file manager

1. Stop the server.
2. Zip your world folder on your PC.
3. Panel → Files → Upload the zip.
4. Unarchive it, then delete the zip.

Match the folder name

server.properties controls which folder is loaded:

level-name=world

Make sure the uploaded folder name exactly matches level-name (case-sensitive on Linux).

Nether & End

Those live in sibling folders:

world/          <- overworld
world_nether/   <- nether
world_the_end/  <- end

Upload all three to keep every dimension.

Verify

Start the server and join — you should spawn where your old world left off. Check the console for Preparing start region without errors.

INFO

If the world was made on Bedrock, it will not load as-is on Java; you need a converter such as Chunker.